


A Lesson in Lust

by clarabellas



Category: Harry Potter - J. K. Rowling
Genre: Detention, M/M, PWP
Language: English
Status: Completed
Published: 2014-10-03
Updated: 2014-10-03
Packaged: 2018-02-19 17:23:34
Rating: Explicit
Warnings: Underage
Chapters: 1
Words: 2,544
Publisher: archiveofourown.org
Story URL: https://archiveofourown.org/works/2396582
Author URL: https://archiveofourown.org/users/clarabellas/pseuds/clarabellas
Summary: <blockquote class="userstuff">
              <p>Severus gets a little more than he bargained for when Harry accidentally makes a lust potion.</p>
            </blockquote>





	A Lesson in Lust

**Author's Note:**

> I am in no way, shape or form affiliated with the Harry Potter universe. That right belongs exclusively to the wonderful J.K. Rowling. 
> 
> That being said, I hope someone enjoys this.

The Potter brat really would be the death of him one day. 

Severus Snape felt a derisive sneer tugging at his lips as he observed the boy frantically work to rectify the potion that was rapidly beginning to bubble out of control. At this stage, the ideal colour for such a potion was a soft lilac. Potter’s was an angry shade of orange. Likely, the boy had forgotten to add the powdered moonstone before bringing his cauldron to the boil. All-in-all, it was not the worst attempt he had ever seen and if Potter acted quickly, it could be saved. All he needed to do was add his chopped peppermint leaves, stir clockwise seven times, before sprinkling in the valerian root and leaving to simmer. Not that he expected him to know this, of course, because it wasn’t in the textbook. 

Severus felt mild surprise as he noticed Potter slide his peppermint leaves into the brew and begin idly stirring. The potion faded to a much less garish shade of orange and began to boil less furiously. Potter himself looked shocked, as well as somewhat hopeful. The boy set down his stirring rod to the side while he appraised his ingredients. 

'The valerian root, boy. You’re almost there!' Severus thought furiously. 

He had often thought that Potter had shown some promise in the field of potions, if only he attempted to apply himself and not get distracted by other students. Perhaps, if the boy salvaged his brew, Severus would refrain from his insults for a few lessons. 

Or perhaps not. 

For some unconceivable reason, it was not his carefully sliced valerian root that he added to the cauldron, but a whole dish of rose thorns. Rose thorns! They were not even on the list of ingredients for the potion, so why they were on his bench was beyond the potions professor. 

“Potter!”

The boy jumped up in alarm, turning the heat on his potion down, before peering up at the man from beneath his fringe. His green eyes glittered in what looked like nervousness. 

“Yes, professor?” The boy asked slowly. 

Severus appraised the contents of the cauldron, shaking his head slightly. Potter had actually succeeded, not in making the set potion, but something else entirely. Instead of a cheerful yellow, the potion was a mauve colour. The colour change was attributed to the addition of rose thorns, which gave the potion entirely different properties. Not so far off a cheering potion, if you thought about it, but not so close that it could be used in front of a room of sixteen-year-old students. 

“What, pray tell, have you concocted for me today?”

Potter took a moment to answer, “A cheering potion, sir?”

“If you took a moment to use that useless thing between your ears, you would notice that your potion is entirely the wrong colour. As such, it is completely useless”, Severus gritted out through bared teeth, “and you will be serving detention with me tonight so that I might demonstrate what this potion does.”

Potter, unusually, did not argue, only nodded with a meek “yes, sir”. Across the room, Draco Malfoy was snickering with Pansy Parkinson. 

“Time is up. Bottle up your work and bring it to me before leaving. That includes you, Potter.”

There was a hum of low chatter as the students set about to packing up their workstations. Severus nodded to several students as they set their phials on his desk before leaving to their next class. The last was Potter, who handed in his work without lifting his head before rushing towards the door. Severus scoffed lightly. He imagined that the brat was imagining many horrible scenarios for his detention this evening. If that were the case, he would be sure to not disappoint. 

“My office at eight this evening. Don’t forget.”

Potter looked back at the professor for only a moment, nodded, and left. Severus shook his head. He doubted Potter realised the true nature of the potion he had made, and Severus really had no intention of harming the boy. No, this potion would at the worst give the boy a healthy dose of embarrassment. Severus was looking forward to it. 

\--

Potter was right on time, for once. 

“Come in.” Severus called from his desk.

The boy shuffled through the door, before closing it quietly. He turned around, but did not move. Severus scowled in annoyance.

“Potter, come here.” He snapped. 

The boy marched towards his professor’s desk, and it please Severus that the boy had fire in his eyes. Severus opened his desk draw and pulled out Potter’s potion, setting it in front of him. He inclined his head toward the phial, an expectant sneer on his face. Potter took a breath before unstoppering the crystal container and knocking it back in one swallow. Now, they would wait. No doubt the boy would start feeling the effects soon. 

It did not take long at all for Potter to start looking uncomfortable. His face was flushing red, and he began to moving from one leg to the other. Severus smiled.

“Stop fidgeting. Do you know what you made today?” Severus asked lowly. 

“No, sir.” Potter replied, voice shaking. 

Severus thought as much. They would not be covering these sorts of potions for another year, and while they had similar ingredients to more common mood potions, they were not in the current textbook. 

“When you added rose thorns to your potion, you inadvertently made yourself a mild lust potion, Mister Potter.” 

The boy’s eyes widened, and the flush extended down his slender neck. His breathing became heavier and his hands clenched. Severus eyed the tell tale bulge in his trousers. Potter shifted his weight from one leg to another in an attempt to hide his arousal, but gasped loudly when the material shifted over his sensitive cock. 

“Is something the matter, Potter?” 

Potter moaned at the sound of his voice and Severus felt his own cock jump in response. Severus eyed the boys heaving chest and lithe body. He had often thought this year that the young Potter was quite desirable, though never had any intention of acting upon this.

“Do you require some…assistance?” Severus asked slowly, before he could stop the words. 

Potter’s face snapped up to look at his professor. His eyes were glistening with desperation but the boy did not respond. Severus stood, grateful that his own loose robes disguised his growing erection, and walked to stand mere inches away from Potter’s tense body. Severus leaned towards the boy, breathing softly against his ear. Potter groaned at the feeling, but otherwise made no move. 

“Answer me, Mister Potter,” The professor murmured. 

“Please, professor!” 

“Please, what?”

“I don’t know!” Potter moaned in frustration, “Touch me, anything…please”.

The last was a whimper and Severus placed a light kiss under the boy’s ear. Potter tilted his head to allow the man better access. Severus nibbled on the skin of his neck, laving the bites with confident strokes of his tongue. The other cried out in pleasure and gripped the older man’s shoulders to steady himself. 

“Are you sure you want me, Harry? Because I’ll make you earn the privilege.”

Harry nodded eagerly, clutching at Severus’s body. The man smirked and ran a hand through the boy’s messy black hair before crashing their lips together in a bruising kiss. Severus ran the tip of his tongue along Harry’s lower lip, coaxing the younger man’s mouth open. He wrapped his arms around the boy’s waist, pulling them closer together and explored his mouth ferociously. They broke apart for a moment, and Severus knew that the boy could feel his arousal against his stomach. Potter did not seem to mind and reached forward to connect their lips once more. The second time was leisurely and gentle. Severus felt a thrill at hearing Harry’s eager moans. Running a hand down the boy’s back, he squeezed his tight ass gently. 

“On your knees, Potter.” Severus gasped after they had broken apart. 

Severus unbuttoned his robes quickly as Potter lowered to the ground and began working on the man’s trousers. Pulling them down, the man’s cock sprang free. Harry gazed upon it in trepidation, eyeing the length and rosy head. Severus caressed the boy’s head in encouragement. Harry licked his lips quickly, before leaning forward and tracing the pink tip of his tongue over the cock head. Severus’s hips bucked forward violently. Harry then placed his mouth over his cock, using his tongue to stroke the underside. The man buried his fingers in Harry’s hair and let out a low groan as the boy hollowed his cheeks and swallowed his cock until it hit the back of his throat.

“Yes, that’s good, Harry.”

The boy flicked his green eyes up to meet Severus’s black, and used his hand to stroke the length of cock that his mouth could not reach. Having Harry on his knees in front of him was one of the most highly erotic things that Severus had witnessed. The boy was also a natural at fellatio, using a mixture of both sucking and licking. Severus began to rock gently into Harry’s mouth. Severus could feel a pressure building at the base of his cock and as the boy began to moan around his length, he could last no longer. He had no intention of ending this here, and reluctantly pulled Potter’s mouth away from his member. 

Severus initiated a passionate kiss with the boy, and pushed him back against his desk. The man tore off Harry’s school robes, discarding them in a heap on the dungeon floor. He loosened the boy’s tie and slowly began to unfasten the buttons of his school shirt; peppering light kisses over his chest. Harry let out a shuddering gasp, clutching the edge of the desk until his knuckles turned white. The shirt and tie jointed his robes on the floor, and Severus paused, hands resting on the buckled of Harry’s belt. 

“I am going to fuck you over my desk, Harry. Do you want that?” Severus said while pressing open-mouthed kisses to Harry’s collar bone. 

Harry nodded.

“What was that, Potter? I didn’t hear you.” The man demanded, thrusting his hips against Harry’s rock hard arousal.  
“Oh! Gods, yes! Please, professor. Fuck me!” Harry cried. 

Severus unbuckled the boy’s belt, and shoved his trousers to his ankles. 

“Step out. Your shoes, too.” The man instructed as he removed his own. 

Severus appraised the young man in front of him, slouched against the dark oak desk, face flushed and cock leaking pre-cum over a quidditch toned stomach. He let out a breath he wasn’t aware he had been holding. The boy was beautiful, and he was all his. 

Severus turned the boy around and leaned him over the desk, placed his hands on the far edge. Potter might want to hold on. He ran his hand over a smooth, unblemished back, tracing each vertebra with a long finger. Harry shivered in anticipation. Severus then ran his hands over the boy’s hips, before resting them on his ass and spreading the cheeks so that he could view the pink pucker between. His ass looked unbelievably tight. 

“Tell me, Potter. Am I your first?” He queried as he teased the boy’s hole.

“Yes.” Harry whispered.

“Good.”

Severus pumped Potter’s cock lazily, smirking at the wanton noises that he was drawing out of the boy. He kissed the boy’s spine before summoning a phial of lubricant. He coated his fingers in the cool substance, before inserting one inside of Harry’s ass. It was as tight as he expected. Harry groaned and pushed back onto his finger eagerly. Severus responded by wiggling his finger gently, until the passage was stretched enough to insert a second appendage. The man began scissoring motions and smiled in satisfaction when Harry jolted and let out a loud moan. 

“Please, more!” he cried out. 

“But of course,” Severus drawled as he inserted a third finger, “but I wonder, Mister Potter. Your potion was hardly strong enough to cause this kind of reaction…” 

Harry gasped at the intrusion and mumbled something into his arm. Severus massaged the young man’s head and let out a questioning hum. 

“Do tell, Mister Potter.” 

“I already wanted you before.”

Harry was heavily flushed, and Severus took a moment to slather his cock with the remaining lubricant in the phial. He lined up his arousal with Potter’s twitching entrance, and pushed in to the hilt with one smooth stroke. He took a moment to let Harry adjust, tracing one hand down the boy’s side in feather light strokes, while the other toyed with his still hard cock. When Harry nodded, Severus pulled back slightly, and then pushed in again. His strokes gradually became longer until he was almost completely withdrawn from Potter’s tight heat, before thrusting back inside fully. The man knew he had hit Harry’s sweet spot when the younger man let out a keening moan, towards which Severus began to aim his thrusts.

The professor seated himself fully inside the boy, and then took a moment to twist Harry’s position. Potter’s back lay flat against the desk, sprawled across scattered parchment. Instinctively, he wrapped his legs around the older man’s waist. The boy turned his face away, but Severus grasped his chin and placed a firm kiss against his lips. Harry invited him inside his mouth without hesitation. Severus slowed his pace, rocking inside Harry with short, but firm strokes, and toyed with a nipple. The younger man moaned inside his mouth and wrapped his arms around his neck.

“I wanted you, too.” Severus murmured in Harry’s ear, punctuating his statement by tapping his cock against his prostate. 

“Please, harder, professor.” Potter whimpered.

Severus could hardly refuse. Lifting the boy’s hips, he aggressively snapped his hips inside the tight passage repeatedly. Slamming against Harry’s prostate with every push, and feeling his release coming, Severus began to fondle the younger man’s cock and balls. Harry came at his touch, crying out and splattering semen over his chest and Severus’s hand. The older man could feel Harry’s entrance fluttering around his cock as he climaxed and soon came inside the boy with one last buck of his hips. 

Severus remained buried inside the boy for a few moments, draped over his chest and lazily kissing his neck. Reluctantly, he withdrew himself. For a moment, he watched his cum trickle out of the boy’s reddened hole, before casting a cleansing spell on both Harry and himself. Potter himself was still collapsed on his desk, breathing deeply. Severus lifted the boy to a standing position and took his lips into one last passionate kiss, carding his long fingers into messier-than-usual hair. He helped the boy dress, and then dressed himself. After this, he went to the door and opened it, gesturing for Potter to leave. 

“But, professor…” Harry started. 

“It is almost curfew, Potter. But perhaps you’d like to come back tomorrow to serve another detention for your…cheek.” The professor smirked. 

Harry’s face lit up in a grin. He jogged to the door, stopping only to brush his hand against the older man’s. As he started down the hallway, Severus called after him,

“Tomorrow at eight. Don’t forget.”

 

FIN


End file.
